study time frame suggests that enzyme inhibition may be occurring or that an extended

incubation time may be required. It has been suggested that persistent drought conditions

may be required before PHE activity increases (Williams et al., 2000b), which appears to

be the situation in this study.

 While the oxidative enzymes do not appear to respond predictably to lowered

water levels, the apparent lignin influence on C mineralization (Ecell/Eox), a function of

the oxidative activities, does exhibit a treatment effect. After initial decreases at 2 weeks,

the Ecell/Eox values increase at a more rapid rate in the dry treatments, especially in

WCA-3A. This suggests that C mineralization in the dry treatments is less negatively

influenced by lignin, which would result in more favorable potential decomposition. This

is less significantly pronounced within ENP-TS, while the WCA-3A benthic layer

exhibits much less lignin influence by 12 weeks.

 The combination of greater C mineralization and lower oxidative enzyme activity

in the WCA-3A cores results in a lower apparent lignin control on C mineralization in

both the benthic and 0 to -10 cm layers. Thus, compared to the ENP-TS cores, the WCA-

3A sediments appear to be more favorable for potential decomposition in terms of lignin

influence and have a greater Ecell:Eox response with lower water levels. Much of this

difference between areas is most probably due to differences in substrate composition

(Williams et al., 2000a), phenolic concentrations (Freeman et al., 2001) and C

availability.

N Mineralization

 Based on other studies, N mineralization was expected to increase in simulated

drought conditions (Reddy and Patrick, 1984; Cabrera 1993; Bridgham et al., 1998;